207 research outputs found

    Monoclonal anti-envelope antibody AP33 protects humanized mice against a patient-derived hepatitis C virus challenge

    Get PDF
    End-stage liver disease caused by hepatitis C virus (HCV) infection is a major indication for liver transplantation. However, immediately after transplantation the liver graft of viremic patients universally becomes infected by circulating virus, resulting in accelerated liver disease progression. Currently available direct-acting antiviral therapies have reduced efficacy in patients with end-stage liver disease and prophylactic strategies to prevent HCV recurrence are still highly needed. In this study we compared the ability of two broadly reactive monoclonal antibodies (mAbs), designated 3/11 and AP33, recognizing a distinct but overlapping epitope in the viral E2 glycoprotein to protect humanized mice from a patient-derived HCV challenge. Their neutralizing activity was assessed using the HCVpp and HCVcc systems expressing multiple patient-derived envelopes and a human-liver chimeric mouse model. HCV RNA was readily detected in all control mice challenged with a patient-derived HCV genotype 1b isolate, while three out of four AP33-treated mice were completely protected. In contrast, only one out of four 3/11-treated mice remained HCV RNA negative throughout the observation period, while the other three had a viral load that was indistinguishable from that in the control group. The increased in vivo efficacy of AP33 was in line with its higher affinity and neutralizing capacity observed in vitro. Conclusion: Although mAbs AP33 and 3/11 target the same region in E2, only mAb AP33 can efficiently protect from challenge with a heterologous HCV population in vivo. Since mAb AP33 efficiently neutralizes viral variants that escaped the humoral immune response and re-infected the liver graft of transplant patients, it may be a valuable candidate to prevent HCV recurrence. In addition our data is valuable for the design of a prophylactic vaccine

    Observed methods of cuneiform tablet reconstruction in virtual and real world environments

    Get PDF
    The reconstruction of fragmented artefacts is a tedious process that consumes many valuable work hours of scholars' time. We believe that such work can be made more efficient via new techniques in interactive virtual environments. The purpose of this research is to explore approaches to the reconstruction of cuneiform tablets in the real and virtual environment, and to address the potential barriers to virtual reconstruction of fragments. In this paper we present the results of an experiment exploring the reconstruction strategies employed by individual users working with tablet fragments in real and virtual environments. Our findings have identified physical factors that users find important to the reconstruction process and further explored the subjective usefulness of stereoscopic 3D in the reconstruction process. Our results, presented as dynamic graphs of interaction, compare the precise order of movement and rotation interactions, and the frequency of interaction achieved by successful and unsuccessful participants with some surprising insights. We present evidence that certain interaction styles and behaviours characterise success in the reconstruction process

    Pivotal Role of the α2A-Adrenoceptor in Producing Inflammation and Organ Injury in a Rat Model of Sepsis

    Get PDF
    Background: Norepinephrine (NE) modulates the responsiveness of macrophages to proinflammatory stimuli through the activation of adrenergic receptors (ARs). Being part of the stress response, early increases of NE in sepsis sustain adverse systemic inflammatory responses. The intestine is an important source of NE release in the early stage of cecal ligation and puncture (CLP)-induced sepsis in rats, which then stimulates TNF-a production in Kupffer cells (KCs) through the activation of the a2-AR. It is important to know which of the three a2-AR subtypes (i.e., a2A, a2B or a2C) is responsible for the upregulation of TNF-a production. The aim of this study was to determine the contribution of a2A-AR in this process. Methodology/Principal Findings: Adult male rats underwent CLP and KCs were isolated 2 h later. Gene expression of a2A-AR was determined. In additional experiments, cultured KCs were incubated with NE with or without BRL-44408 maleate, a specific a2A-AR antagonist, and intraportal infusion of NE for 2 h with or without BRL-44408 maleate was carried out in normal animals. Finally, the impact of a2A-AR activation by NE was investigated under inflammatory conditions (i.e., endotoxemia and CLP). Gene expression of the a2A-AR subtype was significantly upregulated after CLP. NE increased the release of TNF-a in cultured KCs, which was specifically inhibited by the a2A-AR antagonist BRL-44408. Equally, intraportal NE infusion increased TNF-a gene expression in KCs and plasma TNF-a which was also abrogated by co-administration of BRL-44408. NE also potentiated LPS-induced TNF-a release via the a2A-AR in vitro and in vivo. This potentiation of TNF-a release by NE was mediated through the a2A-AR coupled Gai protein and the activation of the p38 MAP kinase. Treatment of septic animals with BRL-44408 suppressed TNF-a, prevented multiple organ injury and significantly improved survival from 45% to 75%. Conclusions/Significance: Our novel finding is that hyperresponsiveness to a2-AR stimulation observed in sepsis is primarily due to an increase in a2A-AR expression in KCs. This appears to be in part responsible for the increased proinflammatory response and ensuing organ injury in sepsis. These findings provide important feasibility information for further developing the a2A-AR antagonist as a new therapy for sepsis

    Exploring gastrointestinal variables affecting drug and formulation behavior: methodologies, challenges and opportunities

    Get PDF
    Various gastrointestinal (GI) factors affect drug and formulation behavior after oral administration, including GI transfer, motility, pH and GI fluid volume and composition. An in-depth understanding of these physiological and anatomical variables is critical for a continued progress in oral drug development. In this review, different methodologies (invasive versus non-invasive) to explore the impact of physiological variables on formulation behavior in the human GI tract are presented, revealing their strengths and limitations. The techniques mentioned allow for an improved understanding of the role of following GI variables: gastric emptying (magnetic resonance imaging (MRI), scintigraphy, acetaminophen absorption technique, ultrasonography, breath test, intraluminal sampling and telemetry), motility (MRI, small intestinal/colonic manometry and telemetry), GI volume changes (MRI and ultrasonography), temperature (telemetry) and intraluminal pH (intraluminal sampling and telemetry)

    Search for Standard Model Higgs Boson Production in Association with a W Boson using a Neural Network

    Get PDF
    Submitted to Phys. Rev. DWe present a search for standard model Higgs boson production in association with a W boson in proton-antiproton collisions at a center of mass energy of 1.96 TeV. The search employs data collected with the CDF II detector that correspond to an integrated luminosity of approximately 1.9 inverse fb. We select events consistent with a signature of a single charged lepton, missing transverse energy, and two jets. Jets corresponding to bottom quarks are identified with a secondary vertex tagging method, a jet probability tagging method, and a neural network filter. We use kinematic information in an artificial neural network to improve discrimination between signal and background compared to previous analyses. The observed number of events and the neural network output distributions are consistent with the standard model background expectations, and we set 95% confidence level upper limits on the production cross section times branching fraction ranging from 1.2 to 1.1 pb or 7.5 to 102 times the standard model expectation for Higgs boson masses from 110 to $150 GeV/c^2, respectively.We present a search for standard model Higgs boson production in association with a W boson in proton-antiproton collisions (pp̅ →W±H→ℓνbb̅ ) at a center of mass energy of 1.96 TeV. The search employs data collected with the CDF II detector that correspond to an integrated luminosity of approximately 1.9  fb-1. We select events consistent with a signature of a single charged lepton (e±/μ±), missing transverse energy, and two jets. Jets corresponding to bottom quarks are identified with a secondary vertex tagging method, a jet probability tagging method, and a neural network filter. We use kinematic information in an artificial neural network to improve discrimination between signal and background compared to previous analyses. The observed number of events and the neural network output distributions are consistent with the standard model background expectations, and we set 95% confidence level upper limits on the production cross section times branching fraction ranging from 1.2 to 1.1 pb or 7.5 to 102 times the standard model expectation for Higgs boson masses from 110 to 150  GeV/c2, respectively.Peer reviewe

    Efficacy, Retention and Tolerability of Everolimus in Patients with Tuberous Sclerosis Complex: A Survey-Based Study on Patients’ Perspectives

    Get PDF
    Background The approval of everolimus (EVE) for the treatment of angiomyolipoma (2013), subependymal giant cell astrocytoma (2013) and drug-refractory epilepsy (2017) in patients with tuberous sclerosis complex (TSC) represents the first disease-modifying treatment option available for this rare and complex genetic disorder. Objective The objective of this study was to analyse the use, efficacy, tolerability and treatment retention of EVE in patients with TSC in Germany from the patient’s perspective. Methods A structured cross-age survey was conducted at 26 specialised TSC centres in Germany and by the German TSC patient advocacy group between February and July 2019, enrolling children, adolescents and adult patients with TSC. Results Of 365 participants, 36.7% (n = 134) reported the current or past intake of EVE, including 31.5% (n = 115) who were taking EVE at study entry. The mean EVE dosage was 6.1 ± 2.9 mg/m2 (median: 5.6 mg/m2, range 2.0–15.1 mg/m2) in children and adolescents and 4 ± 2.1 mg/m2 (median: 3.7 mg/m2, range 0.8–10.1 mg/m2) in adult patients. An early diagnosis of TSC, the presence of angiomyolipoma, drug-refractory epilepsy, neuropsychiatric manifestations, subependymal giant cell astrocytoma, cardiac rhabdomyoma and overall multi-organ involvement were associated with the use of EVE as a disease-modifying treatment. The reported efficacy was 64.0% for angiomyolipoma (75% in adult patients), 66.2% for drug-refractory epilepsy, and 54.4% for subependymal giant cell astrocytoma. The overall retention rate for EVE was 85.8%. The retention rates after 12 months of EVE therapy were higher among adults (93.7%) than among children and adolescents (88.7%; 90.5% vs 77.4% after 24 months; 87.3% vs 77.4% after 36 months). Tolerability was acceptable, with 70.9% of patients overall reporting adverse events, including stomatitis (47.0%), acne-like rash (7.7%), increased susceptibility to common infections and lymphoedema (each 6.0%), which were the most frequently reported symptoms. With a total score of 41.7 compared with 36.8 among patients not taking EVE, patients currently being treated with EVE showed an increased Liverpool Adverse Event Profile. Noticeable deviations in the sub-items ‘tiredness’, ‘skin problems’ and ‘mouth/gum problems’, which are likely related to EVE-typical adverse effects, were more frequently reported among patients taking EVE. Conclusions From the patients’ perspective, EVE is an effective and relatively well-tolerated disease-modifying treatment option for children, adolescents and adults with TSC, associated with a high long-term retention rate that can be individually considered for each patient. Everolimus therapy should ideally be supervised by a centre experienced in the use of mechanistic target of rapamycin inhibitors, and adverse effects should be monitored on a regular basis

    Observation of exclusive charmonium production and gamma+gamma to mu+mu- in p+pbar collisions at sqrt{s} = 1.96 TeV

    Get PDF
    7 pages, 3 figures, 1 table. Version accepted for Phys.Rev.Lett. Phys.Rev.Lett. (to be published)We have observed the reactions p+pbar --> p+X+pbar, with X being a centrally produced J/psi, psi(2S) or chi_c0, and gamma+gamma --> mu+mu-, in proton- antiproton collisions at sqrt{s} = 1.96 TeV using the Run II Collider Detector at Fermilab. The event signature requires two oppositely charged muons, each with pseudorapidity |eta| mu+mu-. Events with a J/psi and an associated photon candidate are consistent with exclusive chi_c0 production through double pomeron exchange. The exclusive vector meson production is as expected for elastic photo- production, gamma+p --> J/psi(psi(2S)) + p, which is observed here for the first time in hadron-hadron collisions. The cross sections ds/dy(y=0) for p + pbar --> p + X + pbar with X = J/psi, psi(2S) orchi_c0 are 3.92+/-0.62 nb, 0.53+/-0.14 nb, and 75+/-14 nb respectively. The cross section for the continuum, with |eta(mu+/-)|In CDF we have observed the reactions p+p̅ →p+X+p̅ , with X being a centrally produced J/ψ, ψ(2S), or χc0, and γγ→μ+μ- in pp̅ collisions at √s=1.96  TeV. The event signature requires two oppositely charged central muons, and either no other particles or one additional photon detected. Exclusive vector meson production is as expected for elastic photoproduction, γ+p→J/ψ(ψ(2S))+p, observed here for the first time in hadron-hadron collisions. We also observe exclusive χc0→J/ψ+γ. The cross sections dσ/dy|y=0 for J/ψ, ψ(2S), and χc0 are 3.92±0.25(stat)±0.52(syst)  nb, 0.53±0.09(stat)±0.10(syst)  nb, and 76±10(stat)±10(syst)  nb, respectively, and the continuum is consistent with QED. We put an upper limit on the cross section for Odderon exchange in exclusive J/ψ production.Peer reviewe

    Search for the Production of Narrow tb Resonances in 1.9 fb-1 of ppbar Collisions at sqrt(s) = 1.96 TeV

    Get PDF
    We present new limits on resonant tb production in proton-antiproton collisions at 1.96 TeV, using 1.9 fb^-1 of data recorded with the CDF II detector at the Fermilab Tevatron. We reconstruct a candidate mass in events with a lepton, neutrino candidate, and two or three jets, and search for anomalous tb production as modeled by W'->tb. We set a new limit on a right-handed W' with standard model-like coupling, excluding any mass below 800 GeV at 95% C.L. The cross-section for any narrow, resonant tb production between 750 and 950 GeV is found to be less than 0.28 pb at 95% C.L. We also present an exclusion of the W' coupling strength versus W' mass over the range 300 to 950 GeV.We present new limits on resonant tb̅ production in pp̅ collisions at √s=1.96  TeV, using 1.9  fb-1 of data recorded with the CDF II detector at the Fermilab Tevatron. We reconstruct a candidate tb̅ mass in events with a lepton, neutrino candidate, and two or three jets, and search for anomalous tb̅ production as modeled by W′→tb̅ . We set a new limit on a right-handed W′ with standard model-like coupling, excluding any mass below 800  GeV/c2 at 95% C.L. The cross section for any narrow, resonant tb̅ production between 750 and 950  GeV/c2 is found to be less than 0.28 pb at 95% C.L. We also present an exclusion of the W′ coupling strength versus W′ mass over the range 300–950  GeV/c2.Peer reviewe
    • …
    corecore